Coherent structure of a d-type rough wall boundary layer in a fully rough regime : analysis with the VITA technique

完全粗面領域におけるd形粗面境界層の組織構造 : VITA法による解析

Coherent structure of a d-type rough wall boundary layer in a fully rough regime : analysis with the VITA technique

Creators Mochizuki Shinsuke

Creators Osaka Hideo

Coherent structure of a d-type rough wall boundary layer at a momentum thickness Reynolds number of R_θ≒5000 has been investigated experimentally. The conditional averaged signals and mean bursting frequency were obtained with the VITA technique. The results show that the bursting phenomenon does exist even in the present rough wall flow. However, the intensity of ejection process is smaller than that of the d-type rough wall flow at R_θ≒800. The mean bursting frequency non-dimensionalized with the wall units takes almost the same value both in the present flow and the smooth wall flow.

[ISSN]0372-7661

[NCID]AN00244228